Use Of Agricultural By-products Research Articles

Active biocompounds to improve food nutritional value

IntroductionConsumers demand natural products, including nutritional supplements, which require a large and continuous supply of active bioactive compounds at a reasonable price. It is for this reason that the use of agricultural by-products as a source of bioactive compounds has shown its potential in different investigations and research projects. ObjectivesTo study and to develop extraction technologies that do not modify the bioactive properties of the bio molecules during its industrial processing or that even improves its activity. MethodsDifferent extraction methodologies are shown. ResultsExtraction methods with non organic solvents have a minimum environmental impact being the best options for natural food ingredients. Fundamental and applied researches are involved in the optimization of extraction technologies and in the study and development of functional foods and nutritional supplements. ConclusionsValorization of wastes from the food industry into active biocompounds is an issue that is becoming more and more important towards the implementation of the Circular Economy, the goal of zero residues and the Clean Label in the European food industries and the health benefits in the European consumers.

Effects of media components and agricultural by-products on γ-polyglutamic acid production by Bacillus toyonensis As8.

Poly-γ‑glutamic acid (γ‑PGA) provides an environmentally friendly alternative to plastic materials which have widely polluted the environment. The microbial production of γ‑PGA, an amino acid biopolymer with glutamic acid subunits, was investigated using renewable agricultural residues in an attempt to find cheaper substitutes for conventional synthetic media components. Bacteria which produce γ‑PGA were isolated through depolymerizing Coix lacryma-jobi, a cellulosic grass, and the effects of various carbon and nitrogen sources, temperature, inoculant load, incubation period, and pH on γ‑PGA yield were determined after submerged fermentation. Bacterial growth was measured turbidimetrically at 550 nm. The γ‑PGA produced was characterized using Fourier transform infrared (FT-IR) spectroscopy and the polymer shape was determined using scanning electron microscopy (SEM). The best γ‑PGA producer was molecularly identified as Bacillus toyonensis As8. The conditions which produced the highest γ‑PGA yield were glucose, ammonium sulfate, 25°C, a pH of 5.5, and an incubation period of 48 h. This bacterium yielded the most γ‑PGA (26.45 g/L) on cassava peels, while other agro-wastes (corn cob, sorghum leaves, Coix noir leaves, and rice bran) also supported bacterial growth with lower γ‑PGA yields than conventional carbon sources. The wrinkled γ‑PGA had absorbance peaks of hydroxyl, amide, carbonyl, and amine groups comparable with the ranges of those found in commercial γ‑PGA. The use of agricultural by-products as fermentation substrates increased γ‑PGA yield and may therefore be used as substitute components in γ‑PGA production.

Use of agricultural by-products in the development of an agro-energy chain: A case study from the Umbria region

Use of agricultural and livestock by-products for anaerobic digestion (AD), in total or partial substitution of the maize silage was evaluated from an environmental and economical point of view. The evaluation process included three methodological interdependent and consequential steps: the chemical stage at laboratory and plant level, the environmental and economic steps developing the Life Cycle Assessment and Life Cycle Costing jointly. The laboratory test showed that the two mixtures prepared with by-products, in partial (MIX A) and total (MIX B) substitution of maize silage, did not show differences in bio-methane production compared to a reference mixture with the 33% of maize silage. All mixtures tested at full-scale plant, showed the same performances, resulting in a similar energy production. Environmentally, MIX B increased greenhouse gas credits derived from the avoided production of mineral fertiliser for the energetic crops, resulting also in better economic performances. The break-even transport distances follow the positive environmental pattern result, in contrast to what was found for the break-even transport distances from the economic point of view.

REPROCESSING OF COMPOSITES BASED ON POLYPROPYLENE LOADED WITH OLIVE HUSK FLOUR

The growing interest in the preservation of our environment stimulates solutions for developing less impacting materials. Thus, the development of composites from renewable resources and recyclable end-of-life resources seems an interesting alternative. This motivated the reason to focus our work on the use of agricultural by-products and waste recycling. Our purpose is the reprocessing of composites based on polypropylene (PP) reinforced with olive husk flour (OHF) at various load rates with adding PP-g-MA as a compatibilizer by six cycles of extrusion. The Young modulus of the composites has slightly increased with the rise of the OHF rate and the number of cycles. An FTIR analysis shows two types of degradation after reprocessing: thermal degradation characterized by a splitting of chains and thermal oxidation justified by the increase in the carbonyl index even when the intensity of the absorption peak has been noticed at 1690–1640 cm–1 referring to the vinyl groups after the 6th cycle. Moreover, the TGA analysis showed a better thermal stability of the composites after the 6th cycle compared to the virgin PP. The rate of crystallization increases with the number of extrusion cycle.

Relationship between feed characteristics and histomorphometry of small intestines of growing pigs

The use of agricultural by-products has become the central focus in reducing feed costs in pig production. However, there is a need to determine how the gastrointestinal tract of pigs responds when subjected to fibrous ingredients. The objective of the study was to predict villi height and apparent villi surface area from physicochemical measurements of maize cob-based diets. Eighteen growing male pigs (initial bodyweight 14.3 ± 1.20 kg) were used in the experiment. The pigs were penned individually and subjected to diets containing 0 g, 80 g, 160 g, 240 g, 320 g, and 400 g maize cob meal/kg diet. Feed and water were provided ad libitum . Using stepwise regression, bulk density (BD) and neutral detergent fibre (NDF) were the best predictor variables influencing villi height (VH) and apparent villi surface area (AVSA). VH produced quadratic and linear responses with BD and NDF, respectively. The equations are VH = 211.3(BD) 2 – 591.0(BD) + 442.4; and VH = 0.03(NDF) + 22.8. Conversely, AVSA produced quadratic and linear responses with NDF and BD, respectively. The equations are AVSA = 0.00036(NDF) 2 – 0.012(NDF) +7.25 and AVSA = - 47.12(BD) + 45.03. In conclusion, the BD and NDF of a feed could be used to predict VH and AVSA of growing pigs fed maize cobs. Keywords : maize cob meal, mucosa lining, physicochemical properties, visceral organs

English

The use of agricultural by-product as feed stock and co-culture fermentation is a good strategy for improving the efficiency of fermentation and ethanol production. Most rice husks have low protein and nitrogen content and need to be supplemented with nitrogen for fermentation process. This research sought to determine the optimal supplementation of rice husk stream–based fermentation medium with nitrogen and molasses sources, initial pH and incubation time for maximizing ethanol production by co-culturing Saccharomyces cerevisiae with Candida tropicalis. Urea, sodium nitrate and ammonium nitrate were used as nitrogen sources and molasses was used as carbon sources. Co-cultures of S. cerevisiae and C. tropicalis can use different nitrogen sources and molasses for growth and ethanol production. Molasses supplemented with rice husk hydrolysate medium, initial pH and incubation period significantly influenced ethanol yield and content of nitrogen and carbon in distillers grains (DDG). Maximum ethanol yield (20.32 ± 0.42%) with nitrogen (4.40 ± 0.11%) and carbon (9.20 ± 1.01%) content of DDG were obtained in the rice husk hydrolysate medium containing 16.0 g/l urea, 12.0 g/l NaNO3, 12.0 g/l NH4NO3, 1.0 g/l KH2PO4, 0.7 g/l MgSO4•7H2O, 20 ml/l molasses, 1.0 g/l KH2PO4 and 0.7 g/l MgSO4•7H2O with initial pH 5.5 and 6 days incubation period at 28 to 29°C, 50% relative humidity in the dark for 5 d in a rotary incubator at 60 rpm. Key words: Rice husk, Saccharomyces cerevisiae, Candida tropicalis, co-culture, ethanol yield, nitrogen and molasses.

An approach for the use of agricultural by-products through a biorefinery in Bangladesh

The global need for developing renewable, sustainable, biomaterials, biochemicals and biofuels continues to grow along with increasing worldwide desire to reduce fossil-fuel emissions. An appealing source for bio-based products is lignocellulosic resources, which are abundant, low cost, and are often a by-product of food production (mainly rice). This paper gives an approach for bio-based product development in Bangladesh by analyzing i) a comprehensive inventory of agricultural and lignocellulosic wastes, ii) the characteristics of these wastes, and iii) suitable methods for producing bio-based products. It is proposed that a cooperative society be set up amongst the rice producing farmers and communities. Entrepreneurs would collaborate with this cooperative society to implement the approach, and biorefinery plants could be established in different parts of the country based on the amount of available agricultural wastes in specific areas. As forest area is very limited and population density is very high in Bangladesh, wood resources cannot be utilized in biofuel, biochemicals and biomaterials production in the country, making agricultural by-products the only real option available.

Day in the Life of Zhongqi He: Research Chemist and Prolific Book Editor

Day in the Life of Zhongqi He: Research Chemist and Prolific Book Editor

Effects of β-mannanase supplementation on growth performance, nutrient digestibility, and nitrogen utilization of Korean native goat (Capra hircus coreanae)

The use of agricultural by-products possessing high β-mannan content as an animal feed ingredient has become increasingly important in achieving cost-effective agriculture. Recent studies showed improvement in growth performance from a diet containing high β-mannan concentrations by the addition of β-mannanase in monogastric animals. Few studies, however, have been conducted to examine the value of β-mannanase supplementation in ruminant diets. In the present study, the effects of β-mannanase supplementation on growth performance, nutrient digestibility, and nitrogen (N) utilization were investigated in growing Korean native goats (Capra hircus coreanae). Twelve Korean native goats (13±1.9kg) were divided into three groups and randomly allocated into one of the following treatments: (1) control (CON), (2) 0.1% β-mannanase supplementation (TRT1), or (3) 0.3% β-mannanase supplementation (TRT2) in a concentrate mix based on dry matter (DM). Diets composed of 40% of tall fescue hay and 60% of each concentrate mix were formulated to meet the National Research Council requirements for indigenous goats. No difference was observed among treatments in terms of DM intake and highest DM and organic matter digestibility (P<0.05) were observed in goats fed CON. However, β-mannanase supplementation significantly increased the average daily gain (P<0.05) and improved feed conversion ratio (P<0.05) as well as N retention (P<0.05). The N intake (P<0.05) and biological value (P<0.10) increased linearly by increasing the dosage of supplementation of β-mannnase. No difference was observed between the two levels of β-mannanase supplementation. In conclusion, β-mannanase supplementation may promote growth and feed efficiency in ruminant animals receiving feedstuffs with high β-mannan concentrations.

Spouted Bed Drying as a Method for Enzyme Immobilization

Usually immobilization is a requirement for the use of enzymes as an industrial biocatalyst. In this work, endophytic fungus Cercospora kikuchii lipase was immobilized by covalent binding on agricultural by-products and microcrystalline cellulose. The enzyme support system was submitted to spouted bed drying. Lipase immobilized on microcrystalline cellulose with 1.5% of glutaraldehyde showed the best results, presenting 179.1% of the original activity after drying, followed by rice husk (173.9%), corn stover (169.8%), sugarcane bagasse (157.3%), green coconut fiber (102.3%), and corncob (99.8%). The immobilized derivatives obtained showed a decreased enzyme activity with an average of only 17.31%, whereas the enzyme in its free form lost 85.8% of its initial activity after storage for 6 months. The operational stability showed that the biocatalysts prepared retained an average of 67.2% of the initial activity after five reuse cycles. The results showed that the use of agricultural by-products as low-cost support material associated with the spouted bed drying is promising and can contribute to industrial application of biocatalysts.

Influence of Yeast-treated Rice By-products on Growth, Yield and Grain Quality of Rice

The use of agricultural by-products as alternative nutrient sources in crop production had gained popularity in order to reducing the rate of chemical fertilizer application in the field. This study was conducted to determine whether the application of rice milling by-products treated with yeast inoculants could substitute, or reduce the rate of chemical fertilizer application. The results of agronomic measurements showed that the effect of incorporated materials was not immediate, as compared to 100% chemical fertilizer application. However, grain yield and quality was either the same or greater than 100% chemical fertilizer application. It was found out that expanded rice hull (treated with yeast or not) could reduce the rate of applying chemical fertilizers by half. Also, yeast treatment was only favorable only to expanded rice hull and not with rice bran, and was already found to be a potential material in reducing chemical fertilizer application in rice production.

Extraction and Neoformation of Antioxidant Compounds by Pressurized Hot Water Extraction from Apple Byproducts

There is a great interest in searching for new environmentally sustainable techniques to enhance the use of agricultural byproducts. In this work, a response surface methodology was used to study the influence of the two independent variables, temperature (25-200 °C) and extraction time (3-17 min), in the extraction of antioxidants by pressurized hot water extraction (PHWE) from industrial apple byproducts. The optimized extraction method for determination of flavonols was at 120 °C and 3 min, giving a predicted total yield of flavonols of 1.3 μmol/g dry apple byproduct. Results obtained suggest that new antioxidant compounds were formed at the higher extraction temperatures. A desirability function response surface, considering maximum antioxidant capacity and minimal formation of brown color, was calculated and gave an optimum of 125 °C and 3 min. This latter PHWE method correlates well with the obtained results for flavonols; thus, a desirability function is a simpler alternative method for finding optimal conditions.

New low cost sorbents for Cr(VI) – batch and column experiments

The use of agricultural byproducts and industrial biowaste materials has been shown to be an attractive technique for removing Cr(VI) from contaminated waste waters. In this study, used brewers draff, peat moss, sawdust, grape stalks and husks were investigated as novel biosorbents for Cr(VI). The material was tested in two different modifications. The material was dried, cut and sieved and part of it was subjected to acid (2 M H2 SO4 ) and alkali (0.5 M NaOH) pre-treatments to remove starch, proteins and sugars. Fourier transform infrared rays analysis on solid phase (FTIR-ATR) was used to determine the main functional groups that might control the metal uptake. Batch experiments were performed at different pH values (3, 4.5, 6) and at various initial concentration of Cr(VI) (25–2012;250 mg L−1 ). Two equilibrium empirical models, Langmuir and Freundlich, were used to describe Cr(VI) adsorption. In order to identify possible reduction processes, ion exchange separation on the AG1-X8 resin was used to separate the anionic Cr(VI) and the reduced cationic Cr(III) from the aqueous phase after biosorption. As expected, Cr(VI) removal was pH-dependent and fitted well both the Langmuir and Freundlich isotherm models. The ion exchange separation showed that Cr(VI) reduction had occurred in the solution during biosorption. The efficiency of draff as a biosorbent was comparable (or even higher) to highly organic materials (e.g., composted peat) showing its potential application for Cr(VI) decontamination.

Bioplastics and GHGs Saving: The Land Use Change (LUC) Emissions Issue

Most life-cycle studies have found that a reduction of greenhouse gas emissions can be achievable by replacing petroleum-based plastics with bioplastics made from renewable feedstock, but these analyses have failed to count the carbon emissions that occur as farmers worldwide convert forest and grassland to new cropland to replace the corn diverted to bioplastics. By excluding emissions from land use change, most previous accountings were one-sided because they counted the carbon benefits of using land for bioplastics but not the carbon costs, the carbon storage, and sequestration sacrificed by diverting land from its existing uses. The accounting for the land use change emissions can limit the attractiveness of bioplastics for the displacement of petroleum-based plastics, at least from an environmental point of view. The use of agricultural by-products as bioplastic feedstock is a valid solution to the problem. Alternatively, recycling of bioplastic wastes could contribute to reducing the land use change emissions. From this point of view, it is clear that the incineration or the landfilling of the bioplastic products are not a valid alternative for a real solution of the problem.

Applications on agricultural and forest waste adsorbents for the removal of lead (II) from contaminated waters

At present, there is growing interest in using low cost, commercially available materials for the adsorption of heavy metals. The major advantages of adsorption technologies are its effectiveness in reducing the concentration of heavy metal ions to very low levels and the use of inexpensive adsorbent materials. In this review, agricultural and forest waste adsorbents were used to remove Pb2+ ions in wastewater treatment, and their technical feasibilities were reviewed in studies mainly from 2000 to 2010. They all were compared with each other by metal binding capacities, metal removal performances, sorbent dose, optimum pH, temperature, initial concentration and contact time. Although commercial activated carbon is widely used in wastewater treatment applications, it has high costs. The use of agricultural by-products as adsorbent material to purify heavy metal contaminated water has become increasingly popular through the past decade because they are less expensive, biodegradable, abundant and efficient. Instead of activated carbon, this study was focused on the inexpensive materials such as agricultural and forest waste. It was shown that these alternative adsorbents had sufficient binding capacity to remove Pb2+ ions from wastewater.

Targeting agricultural research and extension for food security and poverty alleviation: A case study of fish farming in Central Cameroon

Over 5 years of participatory on-farm research, market access, profitability, farming systems productivity and economic sustainability were compared on 100 small-scale farms in Central Cameroon. Integration technology based on the use of agricultural by-products as fishpond inputs was the driver for intensification. Over all farms, fishpond productivity increased from 498 kg to 1609 kg fish/ha (2145 kg/ha/yr). During the project period, the number of active fish farmers increased from 15 to 192 (including 55 farms which participated only through information exchange). Over all farms, net returns from aquaculture increased by 5 times over pre-project levels. Productivity, intensity and profitability increased more significantly in periurban areas with good market access, compared to rural areas. Among farmers with good market access, average net income from the aquaculture enterprise rose from $118 up to $1485. Research-Extension Team (RET) support cost an average of $61,300 per year. Over 5 years, rural farmers recaptured 23% of the relevant RET investment compared to 442% by periurban farmers. Likewise, increase in production attributable to RET intervention was higher for periurban (253%) compared to rural (11.3%) fish farmers. Within 3 years of the end of extension support, rural farmers had returned to pre-project production levels, whereas periurban farms had better maintained their productivity and profitability. Findings indicate that, in areas with little or no access to markets, the number of fishponds and fish farmers can be increased and yields improved, increasing local food supplies, but sustainability in the absence of extension subsidies is questionable. To achieve either of the two principal goals for the sector, food security and/or poverty alleviation, investments need to be made in improving the availability of quality technical assistance to targeted farmers and finding means of reducing social conflict arising from perceived inequalities in the accrual of the benefits of development.

REMOVAL OF HEAVY METAL IONS FROM CONTAMINATED WATER USING CORNCOB-SULPHONATED PHENOL FORMALDEHYDE CONDENSATE

This paper is focused on the use of agricultural by-product as a replacement of the running low cost method for removing heavy toxic and/or radioactive metal ions from water and wastewater. The modification of Egyptian corncobs as a source of low cost plant and recycling material with phenol has been developed in presence of para-formaldedhyde as a cross linking agent. The modification of corncobs was investigated to enhance their natural capacity and could be considered as an added value to the waste plant. In this study, the characterization of the synthesized sulphonated corncob–phenol formaldehyde exchange resin is described and compared with the Dowex HYRW2 –Na polisher cation exchanger. It was found that the synthesized resin is stable in hot water (100oC), mineral acids (2M), in all most common solvents, and alkali solutions 1:0M withstand temperature up to 100oC. The modified corncob resin has an exchange capacity of 2.84 m.eq. /g dry resin –H+ form. The character of copolymer resin adsorption efficiency towards heavy toxic metals has been investigated via different concentrations of Mg (II), Mn (II), Fe (III), Cu (II), Zn (II), Cd (II) and Pb (II) individually in pure aqueous water and aqueous– HCl solutions. Finally a comparison of their removal performance with that of the commercial and the prepared resins was presented in this study where as the last one showed good adsorption efficiency.

Fibers of coffee husk and hulls for the production of particleboard

Recent interest in environment-friendly materials has led to the use of agricultural byproducts as raw material for the production of particleboards. The material used in this study are coffee husk and halls which are residues of coffee processing. Today, these materials are burnt on the field or dumped on land or in rivers. However, they contain a great amount of cellulose and hemicellulose which makes them similar to wood. The study showed that a partial replacement of wood up to 50% is possible at the production of particleboards. Depending on the type and amount of resin, the lab-made particleboards fulfil the requirements of European standards with respect to general use in dry conditions and partly in humid conditions. The results of mechanical, thermal, and hygric testing are presented.

Development of Rice-based Integrated Multiproduct Farming in the Saku Basin in Nagano Prefecture from the 1880s to the 1930s

The purpose of this study is to revisit the beneficial aspects of traditional Japanese integrated multiproduct farming by virtue of its effective use of land resources and agricultural byproducts. As a case study, this paper draws upon a form of multiproduct farming based on rice farming in Sakurai Village in the Saku Basin, Nagano Prefecture, practiced from the 1880s to the 1930s. Although rice cultivation was the major agricultural activity in Sakurai Village, in the 1880s the industry of sericulture was increasing, and by the 1920s it had overtaken rice in terms of production value. Subsequently, however, sericulture entered a period of stagnation due to falling silk cocoon prices, and as a consequence more farmers in the area turned to rice-carp culture (cultivating carp in paddies concurrently with rice). With the introduction of pig farming to the area, the 1930s saw the development of multiproduct farming system consisting of rice, silkworms, carp and pigs. Given that the average farm size per farming family in Sakurai Village was just 65 ares, rice-carp culture was an effective way to make a living from a limited amount of land. Not only was stocking carp in paddies beneficial to the growth of the rice plants themselves, but it cut down on the necessity of weeding. In addition, the silkworm pupae left over from silk production was fed to carp, rice bran to pigs, and barnyard manure became fertilizer for both rice paddies and mulberry fields. In short, this system of rice-based multiproduct farming enabled farmers in Sakurai Village in the 1930s to put small plots of farmland to very efficient use. It is evident that this system was based on the recycling of readily available resources, making efficient use of agricultural byproducts. This rice-based multiproduct system of farming likewise allowed the tenant farming family taken up in this study to actually turn profits, which is evidence that it was an effective means of increasing incomes for the peasantry.

Catalytic pyrolysis of exhausted olive oil waste

The interest on energy recovery from renewable sources is increasing due to the global warming and fossil fuels limitation. Biomass thermochemical conversion methods present some significant advantages such as zero net emissions and the use of agricultural by-products. In this work, a study of the catalytic and non-catalytic pyrolysis of an exhausted olive waste was carried out. The objective was to characterize the solid, liquid and gaseous phases in terms of their energy content. Two experimental series were conducted: uncatalyzed processes, studying the influence of temperature in the range 400–900 °C; and catalyzed ones, investigating the influence of temperature (500–800 °C) and quantity of catalyst (0–100 g). Also, the dolomite effectiveness as catalyst was evaluated. For this motive, consecutive experiments, without reactivating dolomite, were carried out (0–6 runs), and the yields of solids, liquids and gases were determined. It was found that increasing temperature leads in both series to a decrease in the solid and liquid yields and to an increase in the gas yield. The presence and amount of catalyst caused a significant decrease in the liquid phase yield and a high increase in the gas phase yield giving rise to a vast rise in hydrogen production. On the other hand, the catalyst proved to be stable and did not lose activity during at least six pyrolysis cycles. Finally, as a previous step to the design of industrial installations, a kinetic study of the process was performed, based on the generation of the principal gases, considering that these are formed through parallel independent first-order reactions, with different activation energy.